noun
: an art or process of telephonic communication by means of carrier currents over electric conductors (as transmission lines) through the use of transmitting and receiving equipment like those used in radio
noun
: an art or process of telephonic communication by means of carrier currents over electric conductors (as transmission lines) through the use of transmitting and receiving equipment like those used in radio
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012